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arXiv · 2210.03560

Confinement in $QCD$: novelties

Adriano Di Giacomo
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Abstract

We report on recent progress in understanding confinement of colour in $QCD$ as dual superconductivity of the vacuum. A gauge invariant version of the creation operator of monopoles is constructed whose vacuum expectation value is the order parameter. This order parameter is gauge-invariant from scratch, has no infrared divergences, is finite in the confined phase and vanishes in the deconfined phase. A natural explanation also emerges of why the electric field lines in the flux tubes keep no memory of the colour orientation of the condensing monopoles. A further by-product is that the order parameter can be traded with the two-point vacuum parallel correlator of the chromo-electric field.

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Adriano Di Giacomo. 2022-10-07. Confinement in $QCD$: novelties. https://arxiv.org/abs/2210.03560

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